Science & Data

Research of Alaska and Essential Fish Habitat.

We collect information on spawning and breeding grounds, nursery areas and feeding grounds.

Historically, fish scales and otoliths have been the two most common structures used for determining the ages of fish species. Unfortunately, age-readers employing these structures have experienced limited success in the case of Pacific cod.

Research with Otoliths.

Research with Otoliths.

Research with Otoliths.

Age and growth research with otoliths and oxygen isotopes.

Thin sectioning is used to supplement the break and burn method in the age determination of rockfish species and other difficult to age species. The AFSC thin section method is a modified version of a similar thin section technique developed in Australia. The modified thin section was used to develop the ageing criteria for shortraker rockfish and Pacific cod and is currently the primary method used to age shortraker rockfish. Below is a brief description of the procedure along with accompanying photographs.

Learn more about the break-and-burn procedure for studying age and growth of otoliths.

Scientists at the Alaska Fisheries Science Center collect a variety of information about fish that aids in the effective management of commercially important fish and crab stocks.